/*
Copyright 2021 The Vitess Authors.

Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at

	http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
*/

package handlers

import (
	"net/http"

	"vitess.io/vitess/go/vt/vtadmin/rbac"
)

// NewAuthenticationHandler returns an http middleware that invokes the given
// authenticator and calls the next handler in the middleware chain, with the
// authenticated actor added to the request context.
//
// If the authenticator returns an error, then the overall http request is
// failed with an Unauthorized code.
func NewAuthenticationHandler(authenticator rbac.Authenticator) func(http.Handler) http.Handler {
	return func(next http.Handler) http.Handler {
		return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
			actor, err := authenticator.AuthenticateHTTP(r)
			if err != nil {
				http.Error(w, err.Error(), http.StatusUnauthorized)
				return
			}

			next.ServeHTTP(w, r.WithContext(rbac.NewContext(r.Context(), actor)))
		})
	}
}
